Method of processing a proteinous material, a product so obtained, and use thereof

ABSTRACT

The invention relates to a method of removing bovine insulin from a liquid fat-free proteinous material originating from cow&#39;s milk, wherein the liquid fat-free proteinous material originating from cow&#39;s milk, the material having a pH of 2 to 8, at a temperature below 65° C., is contacted with an adsorption resin, whereby the weight ratio of the proteinous material to be treated to the adsorption resin is at most 100:1, optionally combining with said resin treatment at least one ultra and dia-filtration treatment of the proteinous material, and, if necessary, the liquid material so obtained is concentrated into a protein concentrate and optionally dried to powder. The invention further relates to a substantially bovine insulin-free proteinous material so obtained, and to its use as the protein part or raw material in the preparation of substantially bovine insulin-free infant formulae or other special nutritive preparations or consumption milk, other milk drinks or other milk preparations, or as a raw material therein.

The invention relates to a method of processing a proteinous materialmore exactly to a method of removing bovine insulin from a liquidfat-free proteinous material originating from cow's milk. The inventionalso relates to a substantially bovine insulin-free proteinous materialproduced by said method, and to its use as the protein component ofinfant formula or another special nutritive preparation or as the rawmaterial in consumption milk, other milk drinks or different milkpreparations. In the production of said products, the substantiallybovine insulin-free, fat-free proteinous material, which originates fromcow's milk and is produced by said method, can be used as the proteincomponent.

The substantially bovine insulin-free, fat-free proteinous material,preferably whey, which originates from cow's milk and is obtained inaccordance with the invention, is an optimally suitable proteincomponent in the above products, because the processing according theinvention does not substantially alter the taste of the product.

Insulin-dependent diabetes mellitus (IDDM) is a disease caused bydestruction of the insulin-producing beta cells in the Langerhans isletsof the pancreas, while other cells in the islets remain intact (CastanoL. and Eisenbarth G S, Annu. Rev. Immunol, 8 (1990) 647-79 ).

Both genetic and environmental factors are believed to affect the riskof children contracting IDDM. The genetic factor is important, but notsufficient to explain the development of IDDM. Lifetime risk of IDDM isonly between 30 and 50% in one of monozygtic twins, if the other hasIDDM. Only 10% of new IDDM cases occur in families having IDDM, and 90%of new cases are diagnosed in patients with no family history of IDDM.In other words, environmental factors may have an even more importantsignificance than genetic factors in the development of IDDM.

Several epidemiological studies show that exposure to cow's milk proteinin early infancy increases the risk of contracting IDDM (Gerstein H.,Diabetes Care 17 (1994) 13-19). Epidemiological observations have beenused to present several hypotheses concerning mechanisms in which cow'smilk proteins could act as diabetogenic factors. One of the latest is ahypothesis according to which the insulin in cow's milk may cause animmune response which is erroneously directed against the child's owninsulin production (Vaarala, C. Paronen, J. Otonkoski, T. Ákerblom, H.K., Scand. J. Immunol. 47 (1998) 131-135).

Orally administered heterologous insulin, slightly different fromautologous insulin, may violate the immunologic tolerance against betacells. The formation of insulin-identifying lymphocytes may be harmfulin persons having a hereditary susceptibility to IDDM, and theactivation of such a lymphocyte population may later in life result inan auto-immune attack against insulin-producing beta cells. We haveshown that administering a formula to infants induces the production ofantibodies to bovine insulin (Vaarala, O., Paronen, J., Otonkoski, T.,Ákerblom, H. K., Scand. J. Immunol. 47 (1998) 131-135). These antibodiescross-react with human insulin. Since the presence of insulinauto-antibodies (IAA) precedes and predicts the outbreak of IDDM,immunization to insulin, caused by milk products may be harmful andincrease the risk of contracting IDDM. Thus, milk products notcontaining immuno-reactive bovine insulin could be considered to benon-diabetogenic nutrients.

Should the factor activating auto-immunization be bovine insulin, whichis present in small amounts in cow's milk, it is crucially important toremove it from infant formulae in order to prevent the outbreak of IDDMin children. Accordingly, there is a need for commercially availablecow's milk products and cow's milk-based products that do not containimmunoreactive bovine insulin. This relates particularly to infantformulae, which are the first cow's milk-based products consumed byinfants. Additionally, it relates to other special nutritivepreparations and different milk drinks and milk products, such asice-cream, yoghurt and cheese.

Furthermore, it would be desirable that the protein part used in theproducts did not substantially change their familiar taste.

We have previously shown that bovine insulin can be removed from afat-free proteinous material originating from cow's milk, such as wheyor skimmed milk, by means of cation exchange followed by optionalhydrolysis and, after the hydrolysis, optional chromatographictreatment, which may be adsorption resin treatment, for example (Finnishpatent application 971872). Our Finnish patent 94089 also disclosesadsorption resin treatment of a protein hydrolysate.

Not it has been surprisingly found that bovine insulin can be removedfrom a liquid fat-free proteinous material originating from cow's milk,such as whey or skimmed milk directly by means of adsorption resintreatment. This new method removes bovine insulin more completely andeconomically than previously from said proteinous material.

The new method does not even require protein hydrolysis. This avoids theextra costs caused by the hydrolysis step and the change in taste causedby hydrolysis products. The hydrolysis products obtained are splitproteins which change the familiar taste of the product to be produced.For instance milk, whose protein part is at least partly replaced bywhey that is hydrolyzed and therefore contains split proteins, does nottaste like milk. In contrast, milk, whose protein part is at leastpartly replaced by whey treated by the method of the invention andcontaining whole proteins, tastes substantially like milk.

Cow's milk usually contains small amounts of bovine insulin. The contentvaries depending on the assay method but contents of about 1 ng/ml havebeen detected by for example the ELISA method (Enzyme Linked ImmunoSorbent Assay) and the RIA method (Radio Immuno Assay).

In this invention, bovine insulin was assayed from samples by the RIAmethod. The sample solution was frost dried, dissolved in a concentratedsolution and assayed by the RIA. The ELISA method was used as a secondindependent method, wherein the antibodies used were not the same as inthe RIA method. The RIA analysis has to be performed before heattreatment to obtain reliable results. The RIA and ELISA methods gaveresults that were in the same order.

Liquid chromatography and a reversed phase column (Kroeff et al., J.Chromatogr. 461 (1989) 45-61; Poll and Harding, J. Chromatogr. 539(1991) 37-45; Cox, J. Chromatogr. 599 (1992) 195-203; Welinder, J.Chromatogr. 542 (1991) 83-99), gel filtration or an anion exchangecolumn (WO 90/00176 and WO 90/00177) or a weak cation exchange column(DE 3511270 A1 and GB 2173503 A) have usually been employed in thepurification of insulin from production and extraction liquors. None ofthe publications have so far discussed direct separation of bovineinsulin from skimmed milk or whey, except for our aforementioned Finnishpatent application 971872. As such reversed phase or gel filtrationchromatography is not suited to treating milk, since the milk treatedshould be suitable for foodstuffs and reasonably priced.

Insulin can be easily inactivated immunologically with heat treatment.For instance pasteurisation (72° C.) and ultra high treatment (UHTtreatment 135-140° C.) inactivate the majority of the insulin into aform not detectable by the RIA. However, it has been noted that infantswho have been given formulae, have gain immunization to bovine insulinthrough the formulae (Vaarala, O., Paronen, J., Otonkoski, T., Ákerblom,H. K., Scand. J. Immunol. 47 (1998) 131-135), in the production of whichthe majority of the insulin has become non-detectable by the RIA in theheating step.

The applicant has now discovered how to remove bovine insulin moreefficiently than previously from liquid fat-free proteinous materialoriginating from cow's milk. In this case a protein composition isobtained, by reasonable costs, which originates from cow's milk, issuitable for foodstuffs and is substantially free from bovine insulinand is as such suitable for use as the protein part in infant formula inparticular, but also in other special nutritive preparations, or as theraw material in consumption milk, other milk drinks and various milkproducts, such as ice-cream, yoghurt or cheese, and which does notchange their taste from what is familiar.

The method of the invention for removing bovine insulin from a liquidfat-free proteinous material originating from cow's milk ischaracterized by

-   -   contacting the liquid fat-free proteinous material originating        from cow's milk, the material having a pH of 2 to 8, at a        temperature of less than 65° C., with an adsorption resin,        whereby the weight ratio of the proteinous material to be        treated to the adsorption resin is at most 100:1,    -   optionally combining with said resin treatment at least one        ultra and dia-filtration treatment of the proteinous material,        and    -   if necessary, concentrating the liquid material so obtained into        a protein concentrate and optionally drying to powder.

The removal of fat and casein from milk results in whey containing thewhey proteins. Of the total protein of milk, about 20 percent is wheyprotein and the rest is casein. The whey obtained in cheese productionis called cheese whey and the whey obtained in casein production is inturn called casein whey.

The invention is best suited to the treatment of whey. The whey used inthe invention may be any whey originating from cow's milk, such ascheese whey, rennet casein whey, acidic casein whey or sour cheese whey.The whey is preferably cheese whey.

The fat-free proteinous material originating from cow's milk can also beultra and dia-filtrated whey, i.e. a whey protein concentrate. In thiscase the liquid volume to be treated with resin is smaller and thedegree of bovine insulin removal is about the same as in whey treatment.

In addition to the above, skimmed milk or an aqueous solution made fromfat-free milk powder or an aqueous solution made from milk casein i.e. acasein solution, can be used in the invention as the fat-free proteinousmaterial originating from cow's milk. However, in this case the degreeof bovine insulin removal is not in the same order as in whey treatment.

In accordance with the invention, bovine insulin is removed from afat-free proteinous material originating from cow's milk, preferablyfrom whey or a whey protein concentrate, by contacting the material tobe treated with an adsorption resin. A styrene-based on acrylic-basedadsorption resin that is preferably macroporous can suitably be used asthe adsorption resin to which bovine insulin is bound. Suitableadsorption resins include Dowex XUS 40285.00 (pore size about 50 Å;manufacturer Dow Inc., Germany) and Amberlite XAD 7 (pore size between450 and 500 Å; manufacturer Rohm & Haas, France).

Adsorption resin treatment can be carried out either by passing theproteinous material to be treated through a column filled with anadsorption resin, or by contacting said proteinous material with anadsorption resin in a mixing vessel. In adsorption resin treatment, thepH is 2 to 8, suitably 4 to 6.7, and the temperature below 65° C.,usually 2 to 30° C., and suitably 2 to 10° C.

When adsorption resin treatment is carried out in a column, the columnis filled with an adsorption resin, which is suitably regenerated withNaOH and HCl. The proteinous material to be treated is passed through acolumn, filled with the adsorption resin, at a flow rate of 1 to 20column volumes (BV)/h, suitably at a flow rate 6 to 8 BV/h. The weightratio of the proteinous material to be treated in said resin treatmentto the adsorption resin is at most 100:1, suitably 10:1 to 40:1.

When adsorption resin treatment is carried out in a mixing vessel, theadsorption resin regenerated in the above described manner and theproteinous material to be treated are introduced into the mixing vesselin which they are contacted with each other under suitably mild mixing.The weight ratio of the proteinous material to be treated in said resintreatment to the adsorption resin is at most 100:1, suitably 10:1 to40:1, and the duration of the contact is less than 2 hours, suitably 60minutes.

At least one ultra and dia-filtration treatment of the liquid fat-freeproteinous material originating from cow's milk can be combined with theabove adsorption resin treatment. By ultra and dia-filtration the liquidmaterial can be concentrated for drying or other further processing, butsimultaneously the ultra and dia-filtration can be used to complete theremoval of bovine insulin from the material to be treated.Semi-permeable 5,000 to 25,000 D cut-off membranes, suitably 10,000 Dcut-off membranes are used in ultra and dia-filtration. Membranematerials suitable for ultrafiltration include polysulphone,polyethersulphone and hydrophilously coated materials.

The degree of insulin removal obtained by ultra and dia-filtrationincreases as the concentration ratio rises. An appropriate concentrationratio is selected for each particular case.

Whey or some other dilute starting material can be concentrated by theaforementioned ultra and dia-filtration into a whey protein concentrateor into another concentrated starting material, respectively, before theaforementioned adsorption resin treatment. On the other hand, the ultraand dia-filtration can be carried out after the aforementionedadsorption resin treatment, whereby a protein concentrate is obtainedwhich can be dried into powder, suitably by spray or frost drying.

In the treatment of the starting material, the total concentration ratiomay be e.g. about 24 (concentration ratio first 6 and then 4), but inthe concentration of the material into a protein concentrate, the totalconcentration ratio may be e.g. about 120 (concentration ratio first 10and then 12).

In a preferred embodiment of the method of the invention, ultra anddia-filtration is be carried out before and/or after adsorption resintreatment.

Before contact with an adsorption resin, the liquid fat-free proteinousmaterial originating from cow's milk, preferably whey, may be pretreatedby clarifying it at a temperature below 65° C., suitably bymicrofiltration, ultra-filtration or centrifugation. Said pretreatmentis preferably carried out by filtering the material to be treatedthrough microfiltration membranes, the membranes being 0.05 to 1.4micrometer membranes, preferably 0.1 micrometer membranes. In that casecasein dust or denatured whey proteins, which optionally are present,and together with which is a part of the macromolecular proteins towhich insulin is often bound, can be removed particularly from the whey.In ultrafiltration, in turn, membranes with a cut-off value of 50,000 to200,000 D can be used, the speed of rotation in centrifugation beingpreferably between 1,000 and 10,000 rounds per minute.

Clarification treatment also slightly lowers the bovine insulin contentof the material to be treated. The bovine insulin content of whey, forexample, decreases by 6 to 10% in aforementioned clarificationtreatment.

In the most preferred embodiment of the invention, whey is treated by anadsorption resin and this resin treatment is combined with one ultra anddia-filtration treatment that is carried out either before or after theresin treatment. Studies showed that the above procedure resulted in theremoval of bovine insulin from whey by treatment of cheese of caseinwhey with an adsorption resin, such as Dowex XUS 40285.00 (Dow Inc.,Germany) or Amberlite XAD 7 (Rohm & Haas France). By running the whey atpH 2 to 8 through an adsorption resin regenerated with NaOH and HCl, theinsulin was bound to the resin. The whey so treated was ultrafiltered atpH 6.5 to a whey protein concentrate which was evaporated and dried intopowder. The treatment was also carried out by first ultra anddia-filtering the whey and then treating the obtained proteinconcentrate by the adsorption resin. In the treatment, the insulincontent of the whey decreased from 21 to 3 ng/g protein, defined by theRIA, i.e. about 85% in proportion to the protein.

The whey treated in the above manner produced a whey protein preparationwhich, with regard to bovine insulin, was crucially purer than acorresponding conventional infant formula powder (about 22 to 30 ng/gprotein), milk powder (about 30 ng/g protein) or ultra or dia-filteredwhey protein powder (protein content 70 to 80%) (15 to 25 ng/g protein).The substantially bovine insulin-free whey protein preparation soobtained is suitable for use as the raw material and sole protein sourcein infant formulae, since, nutritionally, whey protein is of anextremely high quality and does not need other proteins to complete thenutritional value. Furthermore, the substantially bovine insulin-freeproteinous material obtained according to the invention is suitable foruse as the raw material and protein part in various special nutritionalpreparations, various milk drinks, such as consumption milk, and variousother milk preparations, such as ice-cream, yoghurt and cheese.

Conventionally, infant formulae, the first cow's milk-based productsconsumed by infants, are composed of milk, cream, vegetable oil,low-salt whey powder, minerals and vitamins, of which milk, cream andlow-salt whey powder contain bovine insulin.

The method of the invention allows a substantial reduction in the bovineinsulin content in infant formulae and other cow's milk-based specialnutritive preparations, milk drinks and other milk preparations, and intheir raw materials.

The method of the invention for the preparation of a substantiallybovine insulin-free infant formula or another special nutritivepreparation or consumption milk, another milk drink or another milkpreparation or their raw material is characterized by using asubstantially bovine insulin-free fat-free proteinous materialoriginating from cow's milk and prepared by the method of the inventionas the protein part in the production of a product.

The invention will be described in greater detail in the followingexamples.

EXAMPLE 1

Removal of bovine insulin from whey with a macroporous styrene-basedadsorption resin, Dowex XUS 40285.00 at pH 5.8.

XUS 40285.00 adsorption resin was regenerated with 2% NaOH+2% HCl,rinsed to neutral and packed in a 20-ml column. 20 column volumes (BV),i.e. 400 ml of fresh cheese whey was passed through the column at pH5.8.

In the treatment, 45% of the bovine insulin was removed from the whey.The protein yield in the treatment was 93%, i.e. the insulin contentdecreased by 42% in proportion to the protein.

EXAMPLE 2

Removal of bovine insulin from whey with absorption resin XUS 40285.00at pH values 4, 5.8 and 6.4.

XUS 40285.00 adsorption resin was regenerated with 2% NaOH+2% HCl andrinsed to neutral. 145 ml of cheese whey adjusted to a pH value of 4,5.8 or 6.4 and 25 ml of resin were introduced into an Erlenmeyer flaskplaced in a shaker. After 60 minutes' shaking, the resin was separatedfrom the whey and the bovine insulin content of the whey was assayed bythe RIA.

In the treatment, 57% of the bovine insulin was removed at pH 4.0, 71%at pH 5.8 and 58% at pH 6.4. The protein yield was 69% at pH 4.0, 66% atpH 5.8 and 63% at pH 6.4, i.e. in proportion to the protein, the insulincontent had decreased 39%, 47%, and 37%, respectively. The test showsthat bovine insulin can be removed from whey by an adsorption resinwithin a wide pH range.

EXAMPLE 3

Removal of bovine insulin from whey with a macroporous acrylic-basedadsorption resin, Amberlite XAD 7.

XAD 7 adsorption resin was regenerated with 4% NaOH+0.09% HCl, rinsed toneutral and packed into a 20-ml column. 20 column volumes (BV), i.e. 400ml of fresh cheese whey was passed through the column at pH 6.4.

In the treatment, 76% of the bovine insulin was removed. The proteinyield in the treatment was 90%, i.e. the insulin content had decreased68% in proportion to the protein.

EXAMPLE 4

Removal of bovine insulin from a whey protein concentrate withadsorption resin XUS 40285.00 at pH 5.8.

XUS 40285.00 adsorption resin was regenerated with 4% NaOH+0.09% HCl,rinsed to neutral and packed into a 20-ml column. 20 column volumes(BV), i.e. 400 ml of a microfiltered (1.4 micrometers) whey proteinconcentrate (dry matter 5%, protein 32% of the dry matter) was passedthrough the column at pH 5.8. In the treatment, 46% of the bovineinsulin was removed from the whey protein concentrate. The protein yieldin the treatment was 98%, i.e. the insulin content had decreased 45% inproportion to the protein.

EXAMPLE 5

Removal of bovine insulin from a whey protein concentrate with amacroporous acrylic-based adsorption resin, Amberlite XAD 7.

XAD 7 adsorption resin was regenerated with 4% NaOH+0.09% HCl, rinsed toneutral and packed into a 20-ml column. 20 column volumes (BV), i.e. 400ml of a fresh whey protein concentrate (protein content 2%) was passedthrough the column at pH 6.4.

In the treatment, 86% of the bovine insulin was removed from the wheyprotein concentrate. The protein yield in the treatment was 85%, i.e.the insulin content had decreased 73% in proportion to the protein.

EXAMPLE 6

Removal of bovine insulin from skimmed milk with adsorption resinAmberlite XAD 7 at pH 6.7.

XAD 7 adsorption resin was regenerated with 4% NaOH+0.09% HCl, rinsed toneutral and packed into a 20-ml column. 20 column volumes (BV), i.e. 400ml of skimmed milk (dry matter 9%, protein 35% of the dry matter) waspassed through the column at pH 6.7.

In the treatment, 40% of the bovine insulin was removed in proportion tothe protein. The test shows than bovine insulin can be removed also frommilk, but the degree of insulin removal is lower than in the treatmentof whey.

EXAMPLE 7

Removal of bovine insulin from a casein solution with adsorption resinAmberlite XAD 7 at pH 6.7.

XAD 7 adsorption resin was regenerated with 4% NaOH+0.09% HCl, rinsed toneutral and packed into a 20-ml column. 20 column volumes (BV), i.e. 400ml of sodium caseinate solution (dry matter 3%, protein 89% of the drymatter) was passed through the column at pH 6.7.

In the treatment, 50% of the bovine insulin was removed.

EXAMPLE 8

14 l of fresh cheese whey was ultra and dia-filtered at 40° C. usingGR81PP membranes (6,000 D cut-off membranes) by a Labstak ultrafilter ata concentration ratio of 6, diluted to starting volume and refiltered ata concentration ratio of 4, i.e. the total concentration ratio was 24.The bovine insulin content was assayed by the RIA and the proteincontent was assayed from the starting whey and the whey proteinconcentrate obtained as the end retentate. The starting whey contained21.2 ng of bovine insulin per g of protein, and the whey proteinconcentrate obtained after ultra and dia-filtration contained 14.8 ng ofinsulin per g of protein.

Thus, ultra and dia-filtration reduced the bovine insulin content by 30%in proportion to the protein.

EXAMPLE 9

5.040 kg of whey protein powder made from whey treated in accordancewith example 1, 11.423 kg of a vegetable fat mixture, 11.232 kg ofpurified lactose, 12.260 kg of maltodextrine (DE 21), 135 g of a vitaminand mineral pre-mixture (containing vitamins A, D, E, K, B1, B2, B6,B12, niacin, folic acid, pantothenic acid, biotin, ascorbic acid,choline, inositol, ferrous gluconate, zinc sulphate, manganese sulphate,sodium selenite, copper gluconate), and 70 g calcium chloride, 300 gcalcium phosphate, 65 g magnesium sulphate, 125 g sodium chloride and620 g potassium citrate were dissolved in 60 liters of water (50° C.).The dry matter content of the mixture was about 40%.

The mixture so obtained was led to a homogenizer (150/50 bar) and driedto powder by a spray drier at drying temperatures of 180/75° C. on afluidized bed at 70/120/30° C. The composition, appearance and taste ofthe product were equal to those of a conventional infant formula powder.

1. A method of removing bovine insulin from a liquid fat-free proteinousmaterial originating from cow's milk, said process consisting of thesteps of: contacting the liquid fat-free proteinous material originatingfrom cow's milk with a styrene-based or acrylic-based macroporousadsorption resin having a pore size between 50 to 500 Å, the proteinousmaterial having a pH of 2 to 8, at a temperature of less than 65° C.,whereby the weight ratio of the proteinous material to be treated to theadsorption resin is at most 100:1, wherein an ultra and dia-filtrationtreatment of the proteinous material is carried out before adsorptionresin treatment.
 2. A method of removing bovine insulin from a liquidfat-free proteinous material originating from cow's milk, said processconsisting of the steps of: contacting the liquid fat-free proteinousmaterial originating from cow's milk with a styrene-based oracrylic-based macroporous adsorption resin having a pore size between 50to 500 Å, the proteinous material having a pH of 2 to 8, at atemperature of less than 65° C., whereby the weight ratio of theproteinous material to be treated to the adsorption resin is at most100:1, wherein an ultra and dia-filtration treatment of the proteinousmaterial is carried out before said adsorption resin treatment, andconcentrating of drying the so obtained liquid material into a proteinconcentrate.
 3. A method of removing bovine insulin from a liquidfat-free proteinous material originating from cow's milk, said processconsisting of the steps of: contacting the liquid fat-free proteinousmaterial originating from cow's milk with a styrene-based oracrylic-based macroporous adsorption resin having a pore size between 50to 500 Å, the proteinous material having a pH of 2 to 8, at atemperature of less than 65° C., whereby the weight ratio of theproteinous material to be treated to the adsorption resin is at most100:1, wherein an ultra and dia-filtration treatment of the proteinousmaterial is carried out after adsorption resin treatment.
 4. A method ofremoving bovine insulin from a liquid fat-free proteinous materialoriginating from cow's milk, said process consisting of the steps of:contacting the liquid fat-free proteinous material originating fromcow's milk with a styrene-based or acrylic-based macroporous adsorptionresin having a pore size between 50 to 500 Å, the proteinous materialhaving a pH of 2 to 8, at a temperature of less than 65° C., whereby theweight ratio of the proteinous material to be treated to the adsorptionresin is at most 100:1, wherein an ultra and dia-filtration treatment ofthe proteinous material is carried out after said adsorption resintreatment, and concentrating or drying the so obtained liquid materialinto a protein concentrate.
 5. The method as claimed in claim 1, 2, 3 or4, wherein whey, a whey protein concentrate, skimmed milk or a caseinsolution is the liquid fat-free proteinous material originating fromcow's milk.
 6. The method as claimed in claim 5, wherein whey is theliquid fat-free material originating from cow's milk.
 7. The method asclaimed in claim 1, 2, 3 or 4, wherein the adsorption resin has a poresize between 450 to 500 Å.
 8. The method as claimed in claim 1, 2, 3 or4, wherein the weight ratio of the proteinous material to be treated tothe adsorption resin is 10:1 to 40:1.
 9. The method as claimed in claim1, 2, 3 or 4, wherein the proteinous material is introduced through acolumn, filled with an adsorption resin, at a flow rate of 1 to 20column volumes (BV)/h at a temperature of 2 to 30° C.
 10. The method ofclaim 9, wherein the flow rate is 6 to 8 BV/h.
 11. The method of claim9, wherein the temperature is 2 to 10° C.
 12. The method as claimed inclaim 1, 2, 3 or 4, wherein the proteinous material is contacted withthe adsorption resin at a temperature of 2 to 30° C. in a mixing vessel,whereby the contact time under mild mixing is below 2 hours.
 13. Themethod of claim 12, wherein the contact temperature is 2 to 10° C. 14.The method of claim 12, wherein the contact time is 60 minutes.
 15. Themethod as claimed in claim 1, 2, 3 or 4, wherein the liquid fat-freeproteinous material originating from cow's milk is ultra anddia-filtered using 5,000 to 25,000 D cut-off membranes, before bringingthe proteinous material into contact with the adsorption resin and/orafter the absorption resin treatment.
 16. The method as claimed in claim1, 2, 3 or 4, wherein the liquid fat-free proteinous materialoriginating from cow's milk if pretreated by clarifying it beforebringing it into contact with the adsorption resin.
 17. The method ofclaim 16, wherein clarifying is by microfiltration using 0.05 to 1.4micrometer membranes, ultrafiltration or centrifugation.
 18. The methodof claim 17, wherein clarification is by microfiltration by 0.1micrometer membranes.
 19. The method as claimed in claim 4, wherein theliquid material, treated with the adsorption resin, is concentrated byultra and dia-filtration using 5,000 to 25,000 D cut-off membranes. 20.The method of claim 19, wherein the filtration is by 10,000 D cut-offmembranes.
 21. The method of claim 20, wherein the concentrated liquidmaterial is dried into a powder by spray or freeze drying.
 22. Asubstantially bovine insulin-free, fat-free proteinous materialoriginating from cow's milk prepared by the method of claim 1, 2, 3 or4.
 23. A method of preparing a substantially bovine insulin-free infantformula, nutritive preparation, consumable milk, milk drink, or milkpreparation using as a protein part the substantially bovineinsulin-free, fat-free, proteinous material, originating from cow'smilk, prepared by the method of claim 1, 2, 3 or
 4. 24. A method ofproviding nutrition comprising supplying the substantially bovineinsulin-free, fat-free proteinous material, originating the cow's milk,prepared by the method of claim 1, 2, 3 or 4.